This invention relates to a method of aligning lumber. More particularly, the invention is concerned with the alignment of blocks in which a first pair of cants has been removed.
The lumber is usually obtained in a rough form, as logs, and a first pair of cants is removed from the logs to provide blocks which are to be fed to a saw mill.
The alignment and positioning of the block with respect to the sawing line has an important effect on the amount of full-edged lumber produced from each block. Nowadays the alignment of the block is in practice generally done by hand, based on a visual inspection or an eye-sight calculation only. While using this method, it is very difficult to achieve an optimal result. On the other hand, alignment of the board by hand is a relatively slow process, and it is therefore not suitable for saw mills with a large capacity.
Accordingly, it is an object of this invention to provide a method and a system for rapidly aligning those blocks formed from logs from which the first pair of cants has been removed.
A more specific object of the invention is to align the aforesaid blocks with optimum accuracy without touching the individual blocks with hands.
A further object of the invention is to align lumber, particularly logs or blocks from which the first pair of cants has been removed, in a saw mill before feeding the blocks in alignment with a sawing line in which the block sides are unscrambled and/or the block is divided into cants.
To these ends, the invention consists in the provision of a method of aligning lumber which is made from blocks from which a first pair of cants has been removed to provide for cant-removed blocks hereinafter referred to as blocks for feeding along a sawing line, which comprises charging the (cant-removed) block in a longitudinal direction to pass by a control device, which control device defines the block's side profile and outlines the even sawed surface; after which the block is permitted to fall on its side, and then after the block has fallen on its side, the block is transversely charged against at least two adjustable stops which are positioned in a desired manner according to the above-mentioned information so as to ascertain an optimum amount of wood products at a next processing stage in accordance with the information obtained from the control device.
As a further feature, the block always falls with the same side up, so that the edge which was the upper edge while measuring the block's profile is then transferred against the adjustable stops. The block is passed through a pair of prop rollers situated symmetrically on both sides of the block, and these prop rollers have an inclined surface, with one of the pair of rollers forcing the blocks to fall in the same direction each time.
Accordingly, the blocks will always fall in the same direction. Therefore, the blocks is so controlled that it will and can fall only in one and the same direction.
Other objects, advantages and the nature of the invention will become readily apparent from the detailed description of the invention described in connection with the drawing.